Enbridge wants to increase the line's capacity from the current 570,000 barrels per day to 800,000 by adding new pumping stations.

Judge Eric Lipman concluded Thursday that Enbridge has demonstrated a need for the added capacity. His recommendations now go to the Public Utilities Commission, which must approve major energy projects in Minnesota.

Climate change activists oppose the Alberta Clipper and other Enbridge construction or expansion projects in the works because they carry Canadian tar sands oil. Extracting that oil is an energy-intensive process that generates greenhouse gases.

The Alberta Clipper runs 1,000 miles from Hardisty, Alberta, across northeastern North Dakota and northern Minnesota to Superior, Wis.

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